Air duct structure and air conditioner

Abstract

The application provides a wind channel structure and an air conditioner, and the wind channel structure comprises: a first wind channel, which comprises an inlet diffuser section, a taper section and an outlet diffuser section in sequence along the flow direction of air flow, the inlet diffuser section, the taper section and the outlet diffuser section are sequentially connected, the taper section is located between the inlet diffuser section and the outlet diffuser section, and along the flow direction of air flow, the flow passage area of the inlet diffuser section gradually increases, the flow passage area of the taper section gradually decreases, and the flow passage area of the outlet diffuser section gradually increases. According to the application, noise can be reduced, air can be blown at a long distance, air flow is more stable, the upper wind channel and the lower wind channel are designed through Boltzmann curve equation, vortex and backflow in the wind channel can be eliminated, vortex loss and backflow loss can be reduced, air flow stability of the outlet air channel is improved, fan surge phenomenon is effectively improved, and the flow field is more stable.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of air conditioners, in particular to an air duct structure and an air conditioner. BACKGROUND

[0002] With the continuous improvement of living standards, modern people like to pursue a quiet and comfortable healthy life, and the requirements for air conditioners are also increasing. People not only hope that air conditioners have high performance and large air volume, but also hope that air conditioners have low noise and are energy-saving and environmentally friendly. Distributed air supply air conditioners have obtained high recognition in the air conditioner market due to their unique air outlet mode and fan system performance advantages. Taking distributed air supply technology as the core, the high efficiency and low noise characteristics of centrifugal fans are utilized to establish a bidirectional centrifugal fan air supply system to improve the performance of the centrifugal fan system and reduce the cost of the distributed air supply technology. In combination with the uniqueness of the air supply system, a curved air flow aggregation air supply technology is proposed to control the rotation of the air guide assembly to realize multiple wind feeling experiences such as "fast cooling and heating, wind avoidance mode", and to realize the dual goals of "energy saving" and "comfort". However, the air flow in the bidirectional air outlet air duct is complex, and the vibration caused by the mutual impact of the air flow in the air duct easily produces vortex loss and backflow loss, resulting in low efficiency of the fan and discontinuous aerodynamic noise. Therefore, an innovative design is needed for the bidirectional air outlet air duct and the air outlet characteristics to guide the air flow, improve the efficiency of the fan, and reduce noise.

[0003] Due to the technical problems of the bidirectional air outlet air duct in the prior art, such as complex air flow in the air duct, vibration caused by mutual impact of the air flow in the air duct, vortex loss and backflow loss easily produced in the air duct, low efficiency of the fan, and discontinuous aerodynamic noise, and insufficient air outlet distance and poor air outlet effect, the present application researches and designs an air duct structure and an air conditioner. SUMMARY

[0004] Therefore, the technical problem to be solved by the present application is to overcome the defects of the air outlet air duct in the prior art, such as complex air flow in the air duct, vibration caused by mutual impact of the air flow in the air duct, insufficient air outlet distance, and poor air outlet effect, so as to provide an air duct structure and an air conditioner.

[0005] In order to solve the above problems, the present application provides an air duct structure, which comprises:

[0006] The first air duct comprises, in sequence along the flow direction of the air flow, an inlet diffuser section, a converging section, and an outlet diffuser section. The inlet diffuser section, the converging section, and the outlet diffuser section are sequentially connected. The converging section is located between the inlet diffuser section and the outlet diffuser section. Along the flow direction of the air flow, the flow passage cross-sectional area of the inlet diffuser section gradually increases, the flow passage cross-sectional area of the converging section gradually decreases, and the flow passage cross-sectional area of the outlet diffuser section gradually increases.

[0007] In some embodiments,

[0008] Further comprising a fan, a volute and a second air duct, the fan is arranged inside the volute, the volute comprises a first air outlet and a second air outlet, the first air outlet is located at a first side of the volute, the second air outlet is located at a second side of the volute, the first side is opposite to the second side, the first air outlet is in communication with the first air duct, and the second air outlet is in communication with the second air duct.

[0009] In some embodiments,

[0010] The first air duct is located at the upper end of the volute and forms an upper air duct, and the second air duct is located at the lower end of the volute and forms a lower air duct, and the lower air duct comprises a lower air duct diffuser section.

[0011] The fan is a centrifugal fan, one or both ends of the volute is provided with an air inlet, and the centrifugal fan sucks air into the inside of the volute along the axial direction through the air inlet when operating.

[0012] In some embodiments,

[0013] In the axial projection plane, the upper volute tongue of the volute is c1, the side wall of the upper air duct opposite to the upper volute tongue intersects with the volute at point O, the line connecting point O and the center of the fan is the positive direction of the y-axis, and the x-axis positive direction passing through point O and perpendicular to the y-axis, the x-axis positive direction is located on the same side as the upper air duct, Oa1 is the profile range of the inlet diffuser section and the converging section on the opposite side of the upper volute tongue, and c1b1 is the profile range of the inlet diffuser section and the converging section on the side where the upper volute tongue is located.

[0014] In some embodiments,

[0015] The flow passage cross-sectional area S of the inlet diffuser section and its flow passage length L satisfy the relationship L=(1.8-5)S 2 -(0.8-2.4)S, where S=ab-c 2 Wherein 120≤a≤130, 180≤b≤190; 3.5≤a:c≤3.8, where L is the component length of the inlet diffuser section in the x-axis direction, and c1 is the position where L is 0.

[0016] In some embodiments,

[0017] Oa1 of the upper air duct satisfies the relationship y=A2+(A1-A2) / (1+exp((x-x0) / dx)), where A1=-0.5-9.5, A2=133-141, x0=191-201, and dx=53-57.

[0018] In some embodiments,

[0019] The c1b1 of the upper air duct satisfies the relationship y=A2+(A1-A2) / (1+exp((x-x0) / dx)), where A1=-353 to -153, A2=286 to 296, x0=7 to 67, and dx=99 to 109.

[0020] In some embodiments,

[0021] and 0≤Oa1_x≤368, 0≤b1c1_x≤210, where Oa1_x is the component length of the contour Oa1 in the x direction, and b1c1_x is the component length of the contour b1c1 in the x direction.

[0022] In some embodiments,

[0023] In the axial projection plane, the lower volute tongue of the volute is c2, the side wall of the lower air duct opposite the lower volute tongue intersects the volute at point O, the line connecting point O and the center of the fan is the positive direction of the y axis of the lower air duct, and the x axis positive direction passing through point O and perpendicular to the y axis is on the same side as the lower air duct, Oa2 is the contour range of the diffuser section of the lower air duct on the opposite side of the lower volute tongue, and c2b2 is the contour range of the diffuser section of the lower air duct on the side where the lower volute tongue is located.

[0024] In some embodiments,

[0025] The flow area S of the diffuser section of the lower air duct and the length L of the flow channel L=(5 to 5.5)S 2 -(0.1 to 0.5)S, where S=de, and 120≤d≤150, 180≤e≤190; where L is the component length of the diffuser section of the lower air duct in the x axis direction, and L is 0 at the position of c2.

[0026] In some embodiments,

[0027] The Oa2 of the lower air duct satisfies the relationship y=A2+(A1-A2) / (1+exp((x-x0) / dx)), where A1=-13 to -3, A2=143 to 153, x0=223 to 231, and dx=64 to 74.

[0028] In some embodiments,

[0029] The c2b2 of the lower air duct satisfies the relationship y=A2+(A1-A2) / (1+exp((x-x0) / dx)), where A1=58 to 98, A2=270 to 280, x0=177 to 197, and dx=46 to 66.

[0030] In some embodiments,

[0031] and 0≤b2c2-x≤230, wherein Oa2-x is the component length of the profile Oa2 in the x direction, and b2c2-x is the component length of the profile b2c2 in the x direction.

[0032] The application also provides an air conditioner comprising the air duct structure.

[0033] The air duct structure and the air conditioner provided by the application have the following beneficial effects:

[0034] 1. The application changes the flow area of the air flow in the air duct, and thus changes the flow velocity of the air flow, according to the continuity equation S1V1=S2V2, so that the application establishes the above-mentioned novel non-linear variable flow cross-section air outlet duct, and the flow cross-section and the length of the flow channel change in a non-linear relationship. The upper air duct is divided into a diffuser section, a converging section and an outlet diffuser section. The lower air duct is divided into a diffuser section and an outlet section (according to the design of the lower air outlet component). The above design can improve the stability of the air flow through the inlet diffuser section, improve the flow velocity of the air flow through the converging section, and reduce the noise at the outlet through the outlet diffuser section. The application has the unique three-section structure design, which can reduce noise and achieve long-distance air outlet, so that the air flow is more stable. That is, while achieving the goals of improving air outlet volume and long-distance air supply, the air flow direction in the air duct can also be adjusted to reduce air flow impact loss, improve the air flow field of the fan air duct, reduce the discontinuous aerodynamic noise of the fan air duct, and improve the sound quality experience of the air conditioner.

[0035] 2. The application also sets the inlet diffuser section of the upper air duct to satisfy L=(1.8-5)S 2 -(0.8-2.4)S, which can obtain the best flow field of the air flow, so that the stability is higher and the noise is lower. The formula is dimensionless, i.e., the values on both ends of the formula are dimensionless. The diffuser section of the lower air duct is set to satisfy L=(5-5.5)S 2 -(0.1-0.5)S, which can also make the lower air duct obtain the best flow field of the air flow, so that the stability is higher and the noise is lower. The formula is dimensionless, i.e., the values on both ends of the formula are dimensionless.

[0036] 3. The application further designs the upper air duct as a "narrow type" structure air outlet duct by setting the inlet diffuser section and the tapered section of the upper air duct to meet the Boltzmann curve equation y=A2+(A1-A2) / (1+exp((x-x0) / dx)), i.e. by the Boltzmann curve equation, designs the air duct profile of the bidirectional centrifugal fan by the Boltzmann curve method, eliminates the vortex and backflow in the air duct, reduces the vortex loss and backflow loss, improves the air flow stability of the air outlet duct, effectively improves the fan surge phenomenon, makes the flow field more stable, and further improves the air volume of the fan system.

[0037] 4. The application further designs the lower air duct diffuser section of the lower air duct to meet the Boltzmann curve equation y=A2+(A1-A2) / (1+exp((x-x0) / dx)), i.e. designs the upper air duct by the Boltzmann curve equation, designs a "narrow type" structure air outlet duct, designs the air duct profile of the bidirectional centrifugal fan by the Boltzmann curve method, eliminates the vortex and backflow in the air duct, reduces the vortex loss and backflow loss, improves the air flow stability of the air outlet duct, effectively improves the fan surge phenomenon, makes the flow field more stable, and further improves the air volume of the fan system. BRIEF DESCRIPTION OF DRAWINGS

[0038] Figure 1 is the internal cross-sectional view of the air conditioner of the application;

[0039] Figure 2.1 is the schematic diagram of the air duct structure before and after the Boltzmann function is used in the application (the left diagram is before the design, and the right diagram is after the design);

[0040] Figure 2.2 is the schematic diagram of the air duct structure before and after the Boltzmann function is used in the application on the basis of Figure 2.1 ;

[0041] Figure 3.1 is the schematic diagram of the flow cross section of the upper air duct of the application;

[0042] Figure 3.2 is the schematic diagram of the flow cross section of the lower air duct of the application;

[0043] Figure 4 is the schematic diagram of the upper air duct profile structure of the application;

[0044] Figure 5 is the schematic diagram of the upper air duct profile structure of the application; Figure 4 is the Boltzmann fitting curve diagram of the left and right profile lines of the upper air duct in

[0045] Figure 6is a schematic diagram of the lower air duct line structure of the present application;

[0046] Figure 7 is Figure 6 is a Boltzmann fitting curve diagram of the left and right sides of the lower air duct in

[0047] Figure 8 is a diagram of the airflow velocity distribution of the upper and lower air duct line structures of the present application before and after design (after three-stage air duct design and L-S design, the left diagram is before design, and the right diagram is after design);

[0048] Figure 9 is a diagram of the airflow velocity distribution of the upper and lower air duct line structures of the present application before and after design based on Figure 8 ; (after Boltzmann curve function design, the left diagram is before design, and the right diagram is after design);

[0049] Figure 10 is a diagram of the curve relationship between noise and fan operating frequency of the prior art;

[0050] Figure 11 is a diagram of the curve relationship between noise and fan frequency after the upper and lower air ducts of the present application both adopt Boltzmann fitting line.

[0051] The reference signs are:

[0052] 1, first air duct; 11, inlet diffuser section; 12, taper section; 13, outlet diffuser section; 2, second air duct; 21, lower air duct diffuser section; 3, fan; 4, volute; 41, first air outlet; 42, second air outlet; 5, air guide component; 6, upper air outlet component; 7, air inlet; 8, evaporator; 9, switching mechanism; 10, lower air outlet component; 14, base plate; 15, upper air outlet; 16, lower air outlet. DETAILED DESCRIPTION

[0053] The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all the embodiments. The description of the at least one exemplary embodiment is actually only illustrative, but not as any limitation on the present application and its application or use. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative labor fall within the scope of the present application.

[0054] It is to be understood that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of example embodiments in accordance with the present application. As used herein, the singular forms "a", "an" and "the" are intended to include the plural forms as well, unless the context clearly indicates otherwise. It will be further understood that the terms "comprises" and / or "comprising," when used in this specification, specify the presence of stated features, steps, operations, devices, components and / or combinations thereof, but do not preclude the presence or addition of one or more other features, steps, operations, devices, components and / or combinations thereof.

[0055] The relative arrangement of parts and steps, numerical expressions, and numerical values set forth in the examples are not intended to limit the scope of the application unless specifically so stated. It is also to be understood that the dimensions shown in the drawings are not necessarily to scale, and that the various parts are shown only with the understanding that their dimensions, shapes, and other characteristics can be varied in accordance with the specific application. Techniques, methods, and apparatus known to those of ordinary skill in the relevant art can not be discussed in detail, but should be considered as if they were discussed herein in their broadest form. In all examples shown and discussed herein, any specific value is to be interpreted as illustrative only and not as a limitation on the scope of the application. Thus, other examples of example embodiments can have different values. It is noted that like numbers and letters on the figures identify like parts throughout the several views, and thus, once an item is defined in one figure, it is not necessary to discuss it further in connection with other figures where it is shown.

[0056] In the description of the present application, it is to be understood that the orientation or positional relationships indicated by terms such as "front", "back", "up", "down", "left", "right", "lateral", "vertical", "horizontal", "top", "bottom", and the like are based on the orientation or positional relationships shown in the drawings, and are merely intended to facilitate the description of the present application and simplify the description, and do not indicate or imply that the devices or elements referred to must have a particular orientation or be constructed and operated in a particular orientation, and therefore should not be construed as limiting the scope of protection of the present application. The orientation terms "inner", "outer" refer to the inner and outer relative to the contour of the parts themselves.

[0057] For purposes of the description hereinafter, spatial relative terms, such as "above", "below", "upper", "lower", and the like, can be used to describe the relative position of one element or feature to another as illustrated in the figures. It will be understood that the spatial relative terms are intended to encompass different orientations of the device in use or operation in addition to the orientations depicted in the figures. For example, if the device in the figures is turned over, elements described as "above" or "up" other elements or features would then be oriented "below" or "down" the other elements or features. Thus, the exemplary term "above" can encompass both an orientation of above and below. The device can be otherwise oriented (rotated 90 degrees or at other orientations) and the spatially relative descriptors used herein interpreted accordingly.

[0058] In addition, it should be noted that the use of "first", "second", and the like words of distinction do not connote any meaning of importance, but are used only to distinguish one element from another, and are not intended to denote more, less or the same significance or amount. Thus, the use of such terms is merely intended to distinguish one component from another, and is not intended to connote any specific significance or amount.

[0059] As shown in FIG. 1, Figures 1-11 The present application provides a wind channel structure, which comprises a first wind channel 1, the first wind channel 1 comprising, in sequence along the flow direction of the airflow, an inlet diffuser section 11, a converging section 12 and an outlet diffuser section 13, the inlet diffuser section 11, the converging section 12 and the outlet diffuser section 13 being sequentially connected, the converging section 12 being located between the inlet diffuser section 11 and the outlet diffuser section 13, along the flow direction of the airflow, the flow passage cross-sectional area of the inlet diffuser section 11 gradually increasing, the flow passage cross-sectional area of the converging section 12 gradually decreasing, and the flow passage cross-sectional area of the outlet diffuser section 13 gradually increasing.

[0060] The application establishes the above-mentioned novel non-linear variable flow passage cross-section air outlet air duct, the flow passage cross-section and the length of the flow passage change in a non-linear relationship, the upper air duct is divided into a diffuser section, a converging section and an outlet diffuser section; the lower air duct is divided into a diffuser section and an outlet section (according to the design of the lower air outlet component); the above design can improve the stability of the airflow through the inlet diffuser section, improve the flow rate of the airflow through the converging section, and reduce the noise at the outlet through the outlet diffuser section.

[0061] Referring to Figure 8 The left graph is the traditional one, and the white part is the low flow rate, which produces vortex flow; the right graph is the first improved graph of the application (diffuser + converging + outlet diffuser), which is more stable and has smaller vortex flow.

[0062] The improvement point of the application is that:

[0063] 1. A novel non-linear variable flow passage cross-section bidirectional air outlet air duct is established, the flow passage cross-section and the length of the flow passage change in a non-linear relationship, the target of improving the air outlet flow and long-distance air supply is achieved, the airflow flow field of the fan air duct is improved, the discontinuous aerodynamic noise of the fan air duct is reduced, and the user comfort is improved.

[0064] 2. For the non-linear variable cross-section bidirectional air outlet air duct, an innovative fan air duct design method of Boltzmann function curve is proposed, the bidirectional centrifugal fan air duct profile is designed, and the established Boltzmann curve model is corrected to reduce the vortex loss and backflow loss in the air duct, improve the stability of the airflow flow, and further improve the air volume of the bidirectional centrifugal fan system and reduce the fan surge phenomenon.

[0065] In some embodiments,

[0066] Further comprising a fan 3, a volute 4 and a second air duct 2, the fan 3 is arranged inside the volute 4, the volute 4 comprises a first air outlet 41 and a second air outlet 42, the first air outlet 41 is located at a first side of the volute 4, the second air outlet 42 is located at a second side of the volute 4, the first side is opposite to the second side, the first air outlet 41 is communicated with the first air duct 1, and the second air outlet 42 is communicated with the second air duct 2.

[0067] This is the preferred structure of the air duct structure of the application, that is, the first and second air ducts are respectively communicated by a single fan and a volute structure to operate to blow air from the two air ducts, which can be delivered to different positions to improve the comfort of indoor refrigeration or heating.

[0068] In some embodiments,

[0069] The first air duct 1 is located at the upper end of the volute 4 and forms an upper air duct, and the second air duct 2 is located at the lower end of the volute 4 and forms a lower air duct, and the lower air duct comprises a lower air duct diffuser section 21.

[0070] The fan 3 is a centrifugal fan, one end or both ends of the volute 4 are provided with an air inlet, and the centrifugal fan sucks air into the inside of the volute 4 along the axial direction through the air inlet when operating.

[0071] This is a further preferred structure of the air duct structure of the application, that is, the upper and lower air duct structure and the structure of the centrifugal fan, the centrifugal fan blows air along the axial direction and from the radial direction to the upper air duct and the lower air duct respectively, achieving the purpose and effect of blowing air from the upper and lower air ducts.

[0072] The application provides a fan air duct design method based on a Boltzmann curve function, which is mainly applied to a bidirectional centrifugal fan air supply system, reduces the surge phenomenon of the fan system, and improves the performance of the fan.

[0073] Distributed air supply air conditioners have high recognition in the air conditioning market due to their unique air outlet mode and fan system performance, but the bidirectional air supply fan system is complex in structure, and high-speed airflow is easily impacted in the air duct, vortex loss and backflow loss are easily generated in the air duct, the efficiency of the fan is reduced, and large aerodynamic noise is generated.

[0074] Since the air flow field in the duct is not only affected by the form of the duct, its flow field distribution is also affected by its flow cross-section. According to the continuity equation S1V1=S2V2, it can be known that the flow area of ​​the air flow in the duct can be changed, thereby changing the air flow velocity. The outlet duct is designed with a variable flow cross-section, and its flow cross-section and flow duct length are changed in a nonlinear relationship, divided into a diffusion section, a gradually contracting section and an outlet gradually expanding section; the downwind duct is divided into a diffusion section, and the rest is designed according to the downwind outlet components. The above design can achieve the goal of increasing the air volume and long-distance air supply, and can also adjust the air flow direction in the duct, reduce the air flow impact loss, improve the air flow field in the fan duct, reduce the discontinuous aerodynamic noise in the fan duct, and improve the sound quality experience of the air conditioner.

[0075] In some embodiments,

[0076] In the axial projection plane, the upper volute tongue of the volute 4 is c1, the side wall of the upper air duct opposite to the upper volute tongue intersects with the volute 4 at point O, the line connecting point O and the center of the fan 3 is the positive direction of the y-axis, the direction passing through point O and perpendicular to the y-axis is the positive direction of the x-axis, the positive direction of the x-axis is on the same side as the upper air duct, Oa1 is the profile range of the inlet diffuser section 11 and the tapered section 12 on the side opposite to the upper volute tongue, and c1b1 is the profile range of the inlet diffuser section 11 and the tapered section 12 on the side where the upper volute tongue is located.

[0077] This is the preferred structural form of the upper air duct of the present invention, that is, Oa1 is the profile of the inlet diffuser section and the tapered section on the side opposite to the upper volute tongue, and c1b1 is the profile structure of the inlet diffuser section and the tapered section on the side of the upper volute tongue.

[0078] In some embodiments,

[0079] The flow cross-sectional area S of the inlet diffuser section 11 and its flow channel length LL = (1.8-5)S 2 -(0.8~2.4)S, where S=ab-c 2 , where 120≤a≤130, 180≤b≤190; 3.5≤a:c≤3.8, where L is the component length of the inlet diffuser 11 in the x-axis direction, and c1 is the position where L is 0.

[0080] The present invention designs the inlet diffuser section of the upper air duct to be L=(1.8~5)S 2 -(0.8~2.4)S and the downwind diffuser section is designed to be L=(5~5.5)S 2 The experimental data of -(0.1~0.5)S are as follows in Table 1:

[0081] Table 1

[0082]

[0083] It can be seen from Table 1 that the upper and lower air volume increases by about 50m3 / h at the same noise level (48db) before and after the design, and the noise after the design is lower than the noise before the design at the same air volume; the single upper air volume after the design is increased by about 30m3 / h at the same noise level (47.6db); the noise of the single upper air volume after the design is lower than the noise before the design at the same air volume. The first and second cells in the table refer to the fixed positions of the air guide plate, that is, the wind guide angles are different. The present invention also achieves this by setting the inlet diffuser section of the upper air duct to meet L=(1.8~5)S 2 -(0.8~2.4)S, can obtain the optimal flow field of airflow, making the stability higher and the noise lower. The formula is independent of dimension, that is, both ends of the formula are dimensionless values.

[0084] Parameter design: upper flow channel (above the volute tongue) (see Figure 4 ):1) Diffuser section: The flow cross section of this section gradually increases, which reduces the high-speed airflow velocity from the impeller, reduces the airflow impact vibration, and improves the flow field stability. The relationship between the flow cross section and the flow channel length is L = (1.8 ~ 5) S 2 -(0.8~2.4)S, where S=ab-c 2 , 120≤a≤130, 180≤b≤190; 3.5≤a:c≤3.8; 2) Gradual contraction section: The flow cross-section of this section gradually decreases, increasing the flow velocity to achieve the goal of increasing the air volume and long-distance air supply; 3) The outlet gradual expansion section gradually increases the flow cross-section in the outlet section, reducing the friction and vibration noise between the air flow and the air duct wall and air outlet components, as well as the "rustling sound" of the air outlet, effectively improving the overall sound quality of the air conditioner.

[0085] In some embodiments,

[0086] The Oa1 of the upper air duct satisfies the relationship y=A2+(A1-A2) / (1+exp((x-x0) / dx)), wherein A1=-0.5~9.5, i.e. 4.5-5~4.5+5, preferably -4.56896-1.63674~-4.56896+1.63674, A2=133~141, i.e. 138-5~138+5, preferably 138.36058 -1.33637~138.36058+1.33637, x0=191~201, i.e. 196-5~196+5, preferably 196.42548-1.5823~196.42548+1.5823, dx=53~57, i.e. 55-2~55+2, preferably 55.35882-1.88231~55.35882+1.88231.

[0087] according to Figure 10 and Figure 11 , Figure 10This is the curve relationship between noise and fan speed (frequency) before improvement. Figure 11 The relationship between noise and fan frequency is shown in the curve diagram after the upper and lower air ducts are designed using the Boltzmann curve in the present invention (Bolttzmann curve design is performed on both the upper and lower air ducts). It can be seen that under the same speed and upper and lower air outlet conditions, the total noise value of the present invention can be reduced by about 0.5dB compared with the solution before the improvement. Figure 10 The average noise level is 48.3dB(A). Figure 11 The average noise level is 47.8dB(A).

[0088] The present invention further designs the inlet diffuser section and the tapered section (Oa1 section profile) of the upper air duct to satisfy the Boltzmann curve equation y=A2+(A1-A2) / (1+exp((x-x0) / dx)), that is, designs the upper air duct by using the Boltzmann curve equation, designs an "inclined narrow" structure air outlet duct, and uses the Boltzmann curve method to design the air duct profile of a bidirectional centrifugal fan, which can eliminate vortexes and backflow phenomena in the air duct, reduce eddy current losses and backflow losses, improve the airflow stability of the air outlet duct, effectively improve the fan surge phenomenon, make the flow field more stable, and further increase the air volume of the fan system.

[0089] The values ​​of parameters A1 and A2 determine the vertical distribution width of the function, and the value of parameter dx determines the slope of the curve, so the correction is mainly based on the three parameters A1A2 and dx.

[0090] The present invention proposes a fan duct design method based on the Boltzmann curve. For a centrifugal fan system with up and down air outlets, a nonlinear variable airflow circulation channel is adopted to achieve the goals of increasing the air outlet volume and long-distance air delivery, improving the aerodynamic noise of the fan duct, and improving the performance of the fan system. The nonlinear variable bidirectional air outlet duct is designed with the Boltzmann function to effectively reduce the vortex in the duct, improve the airflow stability of the duct, increase the air volume of the fan system, reduce the fan surge noise, and meet the user's comfortable experience.

[0091] See also Figure 9 , is the airflow velocity distribution diagram of the air duct before and after the Boltzmann curve parameter correction. The left figure is the structure diagram with the first improvement point and without the second improvement point (i.e. Figure 8 The right figure shows the flow field distribution after the first and second improvement points, that is, the figure after the profile is designed by the nonlinear variable flow channel and the Boltzmann function. It can be seen that the dark area is uniform and the range is increased, so the airflow distribution can be more uniform, the vortex is improved, the vortex loss is reduced, the noise is reduced, and the air supply distance and air volume are increased.

[0092] Because the traditional air duct profile design method has been unable to meet the design requirements of the above-mentioned nonlinear variable cross-section bidirectional air outlet channel, the application proposes an innovative Boltzmann curve method for designing the fan air duct, designs the air outlet air duct profile, and corrects the established Boltzmann curve model to design the "narrowly inclined" structure air outlet air duct. The Boltzmann curve method is used to design the profile of the bidirectional centrifugal fan air duct, which can reduce the vortex and backflow phenomenon in the air duct (see Figure 8 、 9 ), improve the airflow stability of the air outlet air duct, effectively improve the fan surge phenomenon, and further improve the air volume of the fan system.

[0093] In some embodiments,

[0094] The c1b1 of the upper air duct satisfies the relationship y=A2+(A1-A2) / (1+exp((x-x0) / dx)), wherein A1=-353 to -153, i.e., -253-100 to -253+100, preferably -253.54113-83.94241 to -253.54113+83.94241, A2=286 to 296, i.e., 291-5 to 291+5, preferably 291.63331-1.49389 to 291.63331+1.49389, x0=7 to 67, i.e., 37-30 to 37+30, preferably 37.30468-25.34168 to 37.30468+25.34168, and dx=99 to 109, i.e., 104±5 to 104+5, preferably 104.48331-4.73362 to 104.48331+4.73362.

[0095] The application further designs the "narrowly inclined" structure air outlet air duct by setting the inlet diffuser section and the converging section (c1b1 section profile) of the upper air duct to satisfy the Boltzmann curve equation y=A2+(A1-A2) / (1+exp((x-x0) / dx)), i.e., by designing the upper air duct through the Boltzmann curve equation. The Boltzmann curve method is used to design the profile of the bidirectional centrifugal fan air duct, which can eliminate the vortex and backflow phenomenon in the air duct, reduce the vortex loss and backflow loss, improve the airflow stability of the air outlet air duct, effectively improve the fan surge phenomenon, make the flow field more stable, and further improve the air volume of the fan system.

[0096] The application provides a fan air duct design method based on a Boltzmann curve, which is mainly applied to a two-way centrifugal fan air supply system. A nonlinear variable cross-section two-way air outlet flow duct is established, a fan air duct design method based on a Boltzmann function is provided, a two-way centrifugal fan air duct mathematical model is established, and the established Boltzmann curve model is corrected, so that the internal airflow flow characteristics of the variable cross-section two-way air duct can be obtained.

[0097] In some embodiments,

[0098] And 0≤Oa1_x≤368, 0≤b1c1_x≤210, wherein Oa1_x is the component length of the profile Oa1 in the x direction, and b1c1_x is the component length of the profile b1c1 in the x direction. This is the preferred size range of the length of the profile Oa1 in the x direction and the preferred size range of the length of the profile b1c1 in the x direction, which effectively designs a profile structure with reduced backflow phenomenon and improved surge.

[0099] In some embodiments,

[0100] In the axial projection plane, the lower volute tongue of the volute 4 is c2, the side wall of the lower air duct opposite to the lower volute tongue intersects with the volute 4 at point O, the line connecting point O and the center of the fan 3 is the positive direction of the lower air duct y axis, and the x axis positive direction passing through point O and perpendicular to the y axis is on the same side of the lower air duct, Oa2 is the profile range of the profile of the lower air duct diffuser section 21 opposite to the lower volute tongue, and c2b2 is the profile range of the profile of the lower air duct diffuser section 21 on the side of the lower volute tongue.

[0101] This is the preferred structure of the lower air duct of the application, that is, Oa2 is the profile of the lower air duct diffuser section opposite to the lower volute tongue, and c2b2 is the profile structure of the lower air duct diffuser section on the side of the lower volute tongue.

[0102] In some embodiments,

[0103] The flow passage cross-sectional area S of the lower air duct diffuser section 21 and the flow passage length L L=(5-5.5)S 2 -(0.1-0.5)S, wherein S=de, and 120≤d≤150, 180≤e≤190; wherein L is the component length of the lower air duct diffuser section 21 in the x axis direction, and c2 is the position where L is 0.

[0104] The application also sets the lower air duct diffuser section to satisfy L=(5-5.5)S 2-(0.1~0.5)S, which is also the best flow field that can make the downwind channel obtain airflow flow, so that the stability is higher and the noise is lower, and the formula is independent of the dimension, that is, the dimensionless value on both ends of the formula.

[0105] The downwind channel (below the volute tongue) of the application (see Figure 6 ) : diffuser section: 1) the relationship between the flow cross section and the length of the channel L = (5~5.5) S 2 -(0.1~0.5)S, wherein S = de, 120≤d≤150, 180≤e≤190.

[0106] In some embodiments,

[0107] The Oa2 of the downwind channel satisfies the relationship y = A2 + (A1-A2) / (1+exp((x-x0) / dx)), wherein A1 = -13~-3, that is, -8-5~-8+5, preferably -7.9946-1.41246~-7.9946+1.41246, A2 = 143~153, that is, 148-5~148+5, preferably 148.12782-2.18997~148.12782+2.18997, x0 = 223~231, that is, 228-5~231, preferably 228.73918-1.99379~228.73918+1.99379, and dx = 64~74, that is, 69-5~69+5, preferably 69.87929-2.39326~69.87929+2.39326.

[0108] The application further designs the "narrow type" structure of the outflow channel by setting the downwind channel diffuser section (Oa2 section type line) of the downwind channel to satisfy the Boltzmann curve equation y = A2 + (A1-A2) / (1+exp((x-x0) / dx)), that is, by designing the upwind channel through the Boltzmann curve equation, and by using the Boltzmann curve method to design the type line of the two-way centrifugal fan channel, the vortex and backflow phenomena in the channel can be eliminated, the vortex loss and backflow loss can be reduced, the airflow stability of the outflow channel can be improved, the fan surge phenomenon can be effectively improved, the flow field is more stable, and the air volume of the fan system is further improved.

[0109] In some embodiments,

[0110] The c2b2 of the lower wind channel satisfies the relationship y=A2+(A1-A2) / (1+exp((x-x0) / dx)), wherein A1=58-98, i.e. 78-20-78+20, preferably 78.15204-16.3495-78.15204+16.3495, A2=270-280, i.e. 275-5-275+5, preferably 275.39267-2.15132-275.39267+2.15132, x0=177-197, i.e. 187-10-187+10, preferably 187.37264-9.06114-187.37264+9.06114, and dx=46-66, i.e. 56-10-56+10, preferably 56.36371-4.61841-56.36371+4.61841.

[0111] The application further designs a "narrowly inclined" structure of the air outlet wind channel by setting the lower wind channel expansion section (c2b2 section curve) of the lower wind channel to satisfy the Boltzmann curve equation y=A2+(A1-A2) / (1+exp((x-x0) / dx)), i.e. by designing the upper wind channel through the Boltzmann curve equation, designs the wind channel curve of the bidirectional centrifugal fan by using the Boltzmann curve method, which can eliminate the vortex and backflow phenomenon in the wind channel, reduce the vortex loss and backflow loss, improve the air flow stability of the air outlet wind channel, effectively improve the fan surge phenomenon, make the flow field more stable, and further improve the air volume of the fan system.

[0112] In some embodiments,

[0113] and 0≤Oa2_x≤395 and 0≤b2c2_x≤230, wherein Oa2_x is the component length of the curve Oa2 in the x direction, and b2c2_x is the component length of the curve b2c2 in the x direction. This is the preferred size range of the length of the curve Oa2 in the x direction and the preferred size range of the length of the curve b2c2 in the x direction of the application, which effectively designs a curve structure with reduced backflow phenomenon and improved surge.

[0114] The application performs Boltzmann function fitting analysis on the wind channel curve of the bidirectional centrifugal fan to design an air outlet wind channel. The upper wind channel curve design (see Figure 4 ) mainly includes the oa1 section (expansion side: above the center of the fan blade, i.e. the B figure of Figure 5 ) and the c1b1 section (volute tongue side: above the volute tongue, i.e. the C figure of Figure 5 ).

[0115] Table 2

[0116]

[0117]

[0118] Down duct line design (see Figure 6 ), mainly including oa2 section (diffusion side: below the center of the fan blade, that is Figure 7 D figure of the application) and c2b2 section (whorl tongue side: below the whorl tongue, that is Figure 7 E figure of the application):

[0119] Table 3

[0120]

[0121] The application also provides an air conditioner comprising the aforementioned air duct structure.

[0122] The application provides a fan air duct design method based on Boltzmann curve function. The method is mainly applied to a bidirectional centrifugal fan air supply system, reduces the surge phenomenon of the fan system, and improves the performance of the fan, and the invention points are as follows:

[0123] 1) According to the continuity equation S1V1=S2V2, the flow area of the air flow in the air duct can be changed to change the flow velocity. A new nonlinear variable flow cross section bidirectional air outlet air duct is established, the flow cross section and the length of the flow channel change in a nonlinear relationship, the upper air duct is divided into a diffusion section, a tapered section and an outlet gradual expansion section; the lower air duct is divided into a diffusion section and an outlet section (according to the design of the lower air outlet part). The above design realizes the goals of improving the air outlet volume and long-distance air supply, and can also adjust the flow direction of the air flow in the air duct, reduce the impact loss of the air flow, improve the air flow field of the fan air duct, reduce the discontinuous aerodynamic noise of the fan air duct, and improve the sound quality experience of the air conditioner.

[0124] 2) For the nonlinear variable cross section bidirectional fan air duct, the application provides an innovative fan air duct design method based on Boltzmann curve method, and establishes a mathematical model of the bidirectional centrifugal fan air duct. Boltzmann curve equation:

[0125]

[0126] Wherein the values of parameters A1 and A2 determine the distribution width of the function in the longitudinal direction, and the value of parameter B determines the inclination of the curve (B is dx in the above formula), so the three parameters A1, A2 and B are mainly corrected.

[0127] Boltzmann function is a commonly used curve function, and the form of the function is: y=A / (1+

[0128] exp((x-x0) / dx)), the air duct design of the application includes four lines, which are Oa1, c1b1, Oa2 and c2b2 of the upper and lower air ducts, so two different coordinate systems are established for calculation.

[0129] The present application carries out Boltzmann function fitting analysis on the variable cross-section two-way centrifugal fan air duct profile, designs the air duct profile, and corrects the established Boltzmann curve model, and designs the "narrow type" structure air outlet duct. The Boltzmann curve method is used to design the two-way centrifugal fan air duct profile, which can eliminate the vortex and backflow phenomenon in the air duct, reduce the vortex loss and backflow loss, improve the air flow stability of the air outlet duct, effectively improve the fan surge phenomenon, and further improve the fan system air volume.

[0130] The above only describes the preferred embodiments of the present application and is not intended to limit the present application. Any modification, equivalent replacement and improvement made within the spirit and principle of the present application shall be included in the protection scope of the present application. The above only describes the preferred embodiments of the present application, and it should be noted that, for ordinary skilled in the art, without departing from the technical principles of the present application, a number of improvements and modifications can be made, and these improvements and modifications shall be considered as the protection scope of the present application.

Claims

1. An air duct structure, characterized by: The wind channel structure comprises: a first wind channel (1) comprising, in sequence along the flow direction of the airflow, an inlet diffuser section (11), a converging section (12) and an outlet diffuser section (13), the inlet diffuser section (11), the converging section (12) and the outlet diffuser section (13) being sequentially connected, the converging section (12) being located between the inlet diffuser section (11) and the outlet diffuser section (13), along the flow direction of the airflow, the flow passage cross-sectional area of the inlet diffuser section (11) gradually increasing, the flow passage cross-sectional area of the converging section (12) gradually decreasing, and the flow passage cross-sectional area of the outlet diffuser section (13) gradually increasing; a fan (3), a volute (4) and a second wind channel (2), the fan (3) being arranged inside the volute (4), the volute (4) comprising a first air outlet (41) and a second air outlet (42), the first air outlet (41) being located at a first side of the volute (4), the second air outlet (42) being located at a second side of the volute (4), the first side being opposite to the second side, the first air outlet (41) being in communication with the first wind channel (1), and the second air outlet (42) being in communication with the second wind channel (2); the first wind channel (1) being located at the upper end of the volute (4) and formed as an upper wind channel, and the second wind channel (2) being located at the lower end of the volute (4) and formed as a lower wind channel, the lower wind channel comprising a lower wind channel diffuser section (21); in the axial projection plane, the upper volute tongue of the volute (4) is c1, the side wall of the upper wind channel opposite to the upper volute tongue intersects with the volute (4) at point O, the line connecting point O and the center of the fan (3) is the positive direction of the y-axis, the line passing through point O and perpendicular to the y-axis is the positive direction of the x-axis, the positive direction of the x-axis is located on the same side as the upper wind channel, Oa1 is the profile range of the inlet diffuser section (11) and the converging section (12) on the side opposite to the upper volute tongue, and c1b1 is the profile range of the inlet diffuser section (11) and the converging section (12) on the side of the upper volute tongue; the flow passage cross-sectional area S of the inlet diffuser section (11) and the flow passage length L thereof, L = (1.8-5)S 2 -(0.8-2.4)S, where S = ab - c 2 where 120≤a≤130, 180≤b≤190; 3.5≤a:c≤3.8, where L is the component length of the inlet diffuser (11) in the x-axis direction, and c1 is the position where L is 0.

2. The wind channel structure according to claim 1, wherein: the fan (3) is a centrifugal fan, one end or both ends of the volute (4) are provided with an air inlet, and the centrifugal fan draws the airflow into the volute (4) through the air inlet along the axial direction when operating.

3. The wind channel structure according to claim 1, wherein: Oa1 of the upper wind channel satisfies the relationship y = A2 + (A1-A2) / (1+exp((x-x0) / dx)), wherein A1 = -0.5-9.5, A2 = 133-141, x0 = 191-201, and dx = 53-57.

4. The wind channel structure according to claim 1, wherein: The c1b1 of the upper air duct satisfies the relationship y=A2+(A1-A2) / (1+exp((x-x0) / dx)), where A1=-353 to -153, A2=286 to 296, x0=7 to 67, and dx=99 to 109.

5. The air duct structure according to claim 3, wherein: 0≤Oa1_x≤368 and 0≤b1c1_x≤210, where Oa1_x is the component length of the profile Oa1 in the x direction, and b1c1_x is the component length of the profile b1c1 in the x direction.

6. The air duct structure according to claim 1, wherein: In the axial projection plane, the lower volute tongue of the volute (4) is c2, the side wall of the lower air duct opposite to the lower volute tongue intersects the volute (4) at point O, the line connecting point O and the center of the fan (3) is the positive direction of the y axis of the lower air duct, and the x axis positive direction passing through point O and perpendicular to the y axis is on the same side of the lower air duct as the x axis positive direction, Oa2 is the profile range of the diffuser section (21) of the lower air duct on the side opposite to the lower volute tongue, and c2b2 is the profile range of the diffuser section (21) of the lower air duct on the side where the lower volute tongue is located.

7. The air duct structure according to claim 6, wherein: The flow area S of the diffuser section (21) of the lower air duct and the flow path length L thereof satisfy the relationship S / L=0.5+0.5 / (1+exp((x-x0) / dx)), where x0=0.5 to 1.5 and dx=0.5 to 1.

5. L = (5-5.5)S 2 - (0.1-0.5)S, with S = de, where 120≤d≤150, 180≤e≤190; where L is the component length of the diffuser (21) in the x-axis direction and L is 0 at the position at c2.

8. The air duct structure according to claim 6, wherein: The Oa2 of the lower air duct satisfies the relationship y=A2+(A1-A2) / (1+exp((x-x0) / dx)), where A1=-13 to -3, A2=143 to 153, x0=223 to 231, and dx=64 to 74.

9. The air duct structure according to claim 6, wherein: The c2b2 of the lower air duct satisfies the relationship y=A2+(A1-A2) / (1+exp((x-x0) / dx)), where A1=58 to 98, A2=270 to 280, x0=177 to 197, and dx=46 to 66.

10. The air duct structure according to claim 8 or 9, wherein: 0≤Oa2_x≤395 and 0≤b2c2_x≤230, where Oa2_x is the component length of the profile Oa2 in the x direction, and b2c2_x is the component length of the profile b2c2 in the x direction.

11. An air conditioner characterized by comprising: An air duct structure according to any one of claims 1 to 10.

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